Casting-machine



Patented Feb. 22,1921.

J. MAYER-OAKES.

CASTING MACHINE.

APPLICATION FILED JUNE 1. 1920.

ATTORNEYS JOSHUA MAYER-CAKES, on NEW HAVEN, CONNECTICUT.

CASTING-MACHINE.

Specification of Letters Patent.

Patented Feb. 22, 1921.

Application filed June 7, 1920. Serial No. 386,979.

T 0 all whom it may concern:

Be it known that I, JosHUA MAYER- OAKES, a citizen of the United States, re-' siding at New Haven, county of New Haven,

State of Connecticut, have invented an Improvement in Casting-Machines, of which the following is a specification; V

This invention relates to metal casting machines of the compressed air variety which are especially adapted for use by clentists, as in the casting ofinlays, crowns, bridges, saddles, and the like, and has for its object to improve generally machines of this character, particularly with respect to the means for locking the cap to the flask, for fusing the metal to be cast, and for forcing the fused metal into the mold.

With the above and other objects in View, the invention comprises the construction, arrangement and operation of parts as now to be fully described and hereinafter specifically claimed.

In the accompanying drawing forming a part of this specification,

Figure 1 is a side elevation of the casting machine of the invention;

Fig. 2 a side elevation,-partially in section, showing the cap and plunger locked in depressed position;

Fig. 3 a vertical section of a portion of the machine;

Fig. 4 an elevation of the air pressure gages detached; and

Fig. 5 is a vertical section of a modified form of base plate, showing a flask adapter as used in connection therewith.

The base plate of the machine, shown in Figs. 1, 2' and 3, and denoted by 10, is recessed to receive a flask 11 of ordinary or preferred form which is providedwith the usual'investment material 12 having therein a crucible shaped depression 13 for'the metal to be fused and a sprueway 14 leading to the mold. A vent 15 through the base plate opens to the investment to allow particles of air which are forced from the mold and into the investment to escape. A standard 16 extending from the base plate carries an overhanging arm 17 having extending upwardly therefrom a pair of spaced apart supports 18. r

The portion of theupper faceof the overhanging arm which lies between the bases of the supports is flat, as indicated by 19 in Fig. 2, and is provided with a shoulder 20.

A vertical opening extending through the arm 1s adapted to slidably receive a plunger 21 the upper end of whichis positioned between the spaced apart supports and is pivotally attached as indicated at 57 to an operating lever 22 which has an inner end 23, preferably shaped about as shown. A link 24 has one of its ends pivoted between the upper ends or the supports, as indicated at 25, and its other end pivoted, as shown at 26, to the inner end of the operating lever. It w ll be apparent that the arrangement provldes a toggle which may be manipulated by the operating lever to actuate the plunger. The overhanging arm is also provided with a horizontahopening, denoted by 27, which communicates with the vertical opening and is adapted to carry a friction device consisting of a sliding plug 28 and a compresslon spring 29 which is adapted to push the plug against the plunger to hold it in any position in which it may be placed. A thumb nut 30 screwed to a cylindrical, threaded extension 31 on the overhanging arm and positioned over the opening is adapted to hold the compression spring and plug in the horizontal opening, as will be understood.

The plunger carries the hub, denoted by 32 of a cap 33 which is adapted to closely fit upon the upper edge of the flask as is usual 1n machines of this character. 34 denotes asbestos or other h at resisting material upon the bottom of the cap. As shown more clearly in Fig. 3, the hub is socketed in the plunger so that there will be play between these parts. A lug 35,-extending from the hub and into a vertical guide 36 in the plunger, prevents the cap from rotating. The hub is provided with a vertical, centrally arranged opening which is adapted to receive a valve stem 37 carrying a conical valve 38, and the lower end of the vertical opening diverges-into a conically shaped valve the compressed air is supplied. An opening extending through the hub and neck and communicating with the compressed air tube enters the conical valve seat at about the point indicated at 4:6 in Fig. 3.

A blow pipe a7, pivoted to the standard as indicated at l8 and having communication with a flexible pipe 49, is adapted to provide the flame whereby the metal in the crucible shaped depression can be fused. The blow pipe carries a tip and an automatic shut-off valve 51, both for a purpose to be explained. A support arm 52 secured to the standard as indicated at 53 carries pressure gages, 54: denoting a gage for showing the pressure in the compressed air tube,

a gage for showing the reserve air pressure, and 56 a reduction valve between the gages.

The operation of the machine is as follows: When the operating lever is friction ally held in the position shown in Fig. 1 and the unformed metal is in the crucible shaped. depression the blow pipe is adapted to carry the flame to the metal and fuse it in usual manner. vVhen now the operating lever is swung to the position shown in Fig. 2, the plunger and cap are moved downwardly so that the cap rests upon the upper edge of the flask. It will be apparent that continued downward movement of the op erming lever will cause the lower endoi the plunger to slide downwardly on the hub against the pressure of the coil spring carried by the valve stem, and will also firmly seat the cap upon the upper edge oi the flask. In view oi the fact that the valve stem is carried by the plunger and is slidable in the hub, the downward movement of the plunger on the hub causes the valve to he removed from its conical seat. as will be clear. This, it will be evident, provides communication between the compressed tube and flask. By a ranging the opening from the compressed air tube so that it enters the wall of the conical valve, as disclosed in 3, a more satisfactory arrangement than has heretofore existed is provided. No air is perm'tted to escape, and the conical valve acts as a deflector for the air so that the pressure against the fused metal is uniform over the entire surface of the metal. The tip carried by the blow pipe is so arranged that it is deflected by the outer edge of the cap, as the latter is moved downwardly, to the inoperative position or? the blow pipe, as shown more clearly in Fig. 2. The shut-off valve is thus closed and the flame extinguished.

' The toggle arran ement, as shown in Fig. 2, provides locking means for the plunger when it has been thrown to the depressed position of the cap, for the reason that the operating lever is supported by the upper face of the overhanging arm in. such position that the inner end of said lever and the link, as well as their pivots, are in alinement with each other and with the plunger, as clearly disclosed.

In Fig. 5, l have shown a modified form of base plate provided with dowel pins 58 which are adapted to support a flask adapter whereby flasks of varying sizes may be held in proper position to be engaged by the cap when it is depressed. As shown the adapter consists ot'a block 59, the opposite sides of which are constructed to accommodate flasks of different sizes. Vent 60 in the adapter opens to the investment.

Vhat I claim is:

1. In a machine of the character described, a flask, an arm arranged thereover, a plunger slidably arranged in the arm and carrying a cap which is adapted to rest on the flask, a toggle carried by the arm and pivoted to the plunger which automatically locks the plunger in its lowest position, and means for actuating the plunger.

2. In a machine of the character described, a flask, an arm arranged thereovcr, a plunger slidably arranged in the arm and carrying a cap which is adapted to rest on the flask, a toggle carried by the arm and pivoted to the plunger and locking it in its lowest position, an operating lever extending from the toggle, and means whereby the plunger may be frictionally held in any position in which placed.

In a machine of the character described, a flask, an arm arranged thereover, a plunger slidably arranged in the arm and carrying a cap which is adapted to rest on the flask, a toggle carried by the arm and pivotedv to the plunger and looking it in its lowest position, and an operating lever for the plunger which is adapted to rest on the arm, whereby the cap can be locked to the flask.

4. in a machine of the character described, a flask, an arm arranged thereover, a plunger slidably arranged in the arm and carrying a cap which is adapted to rest on the flask, a toggle carried by the arm and pivoted to the plunger and locking it in its lowest position, means for actuating the plunger, and means whereby the plunger may be frictionally held in any position in which placed.

5. In a machine of the character de-. scribed, a flask, an arm arranged thereover, a plunger slidably arranged in the arm and carrying a cap which is adapted to rest on the flask, a toggle carried by the arm and pivoted to the plunger and locking it in its lowest position, so that the cap can be locked to the flask.

6. In a machine of the character described, a flask, a plunger carrying a cap which is adapted to rest on the flask, a toggle connection for actuating the plunger and continuously acting means for frictionally holding the plunger in any position in which placed.

7. In a machine of the character described, a flask, a plunger carrying a cap which is adapted to rest on the flask, a toggle connection for actuating the plunger, an operating lever, means whereby the cap may be locked to the flask, and a continuously acting friction device adapted to hold the plunger in any position in which placed.

8. In a machine of the character described, a plunger, a flask, a cap therefor, a hub by which said cap is carried, a conically shaped valve seat arranged in said cap, a valve adapted to normally rest against said seat, said valve normally holding the hub and cap together and to be removed therefrom, said hub rovided with an opening which enters the wall of said valve seat, and compressed air conveying means which is adapted to communicate with the opening in said hub, whereby air under pressure may be communicated directly to said flask.

9. In a machine of the character described, a flask, a cap therefor, a hub by which said cap is carried, and a plunger carrying said hub and adapted to slide thereon, said cap having arranged therein a conically shaped valve seat, said plunger having extending therefrom a valve stem carrying a valve which is adapted to fit said valve seat, and said hub provided with a vertical opening which is adapted to receive said valve stem whereby the plunger and hub are connected and further provided with an opening which enters the wall of said valve seat, and compressed air conveying means which is adapted to communicate with the opening in said hub, whereby air under pressure may be communicated directly to said flask.

10. In a machine of the character described, a flask, a plunger, a hub, a cap, said hub being carried by said plunger, a

combined valve stem, valve and retainin member for said hub extending from sai plunger and holding it and the hub together, toggle operating means for said plunger, means for automatically locking the toggle and plunger in lowest position at which position said cap shall be locked to the flask, and means for automatically holding the plunger and connected parts at other than locked position.

11. In a machine of the class described, a flask, a cap therefor, a hub by which said cap is carried, a plunger carrying said hub with sliding portions between, a valve stem upon which the hub moves, a valve retaining the hub on the plunger, a spring between the plunger and hub, normally hold: ing the hub against the valve, a vave seat in said hub co-acting with said valve, an air passage in the valve seat, and air conveying means connected therewith, said valve controlling the entrance of air to the flask, and from the compressed air conveying means at the same time and immediately distributing the air passing to the flask.

12. In a machine of the class described, a flask, a cap therefor, a hub by which said cap is carried, a plunger carrying said hub with sliding portions therebetween, a valve stem upon which the hub moves, a valve retaining the hub on the plunger, the valve seat on said hub co-acting with said valve, an air passage in the valve seat, air conveying means connecting therewith, said valve controlling the entrance of air to the flask and from the compressed air conveying means at the same time, and immediately distributing the air passing to the flask.

In testimony whereof I aflix my signature.

JOSHUA MAYER-CAKES. 

